Various proposals have been made heretofore for providing a lining for a furnace and the like high temperature chambers avoiding the disadvantages of rigid refractory materials such as bricks and cast components. Such proposals involve the use of refractory fibers formed into mats, blankets and other configurations. The refractory or ceramic fibers are customarily laid down in randomly arranged layers interbonded to one another at points of cross over. Typically, chambers insulated with refractory fibers operate in a temperature range of 1,600.degree. to 2,800.degree. F. and satisfactory insulation utilizing refractory fibers requires an insulation thickness of 4-6 inches or more. If blankets of such fibers are applied with the layers lying generally parallel to the chamber wall, serious problems are encountered including those of securing blankets to the wall and particularly the problem of delamination or peeling off of successive surface layers progressively and after a relatively short service life. To avoid these problems and others associated therewith it has been the practice to utilize a wide variety of arrangement in which blankets of fibers one to two inches thick are secured to the chamber wall with the fiber layers lying in planes generally normal to the chamber wall. This avoids the serious delamination and spalling problems but presents other problems associated with the assembly of liner modules or components formed of multiple layers held assembled in side-by-side relation and provided with suitable heat resistant means for securing the assembly to the chamber wall. Patents in this art dealing with these problems and proposing different solutions include: Sauder et al, U.S. Pat. No. 3,819,468; Balaz et al, U.S. Pat. No. 3,832,815; Brady, U.S. Pat. No. 3,854,262; Monaghan, U.S. Pat. No. 3,892,396; Sauder et al, U.S. Pat. No. 3,940,244; Byrd, U.S. Pat. No. 3,952,470; Byrd, U.S. Pat. No. 4,001,996; Byrd, U.S. Pat. No. 4,012,877; Byrd, U.S. Pat. No. 4,103,469; Myles, U.S. Pat. No. 4,120,641; Byrd, U.S. Pat. No. 4,123,886; Cunningham et al, U.S. Pat. No. 4,218,962; Severin et al, U.S. Pat. No. 4,287,839 and Hounsel et al, U.S. Pat. No. 4,381,634.
The two Sauder patents propose a complex module assembly formed of a multiplicity of individual strips of refractory fiber bonded along one edge to expanded metal backing or held assembled to a backing layer of fibers by means of a complex series of tie wires criss crossing one another. The several Byrd patents show different techniques for folding a ceramic blanket with certain folds embracing an elongated anchor member provided with tang means protruding outwardly through the fold with its outer end clenched to an elongated mounting strip securable to a furnace wall.
The Cunningham and Housel patents show closely related variants of the several Byrd teachings. Balaz and Brady both propose modules composed of separate strips of refractory fibers required to be assembled in side-by-side relation and held assembled by a plurality of pins on which all strips are impaled and secured to retaining members at the opposite ends of the pins. Brady's clamping pins are staggered relative to one another and the retaining members are secured to a mounting plate coextensive with the outer edges of the strips and securable to a furnace chamber, whereas Palaz extends his pins through eye bolts employed to clamp the modules to the chamber wall. Monaghan secures one end of L-shaped mounting hooks to the chamber wall and having a pointed leg extending upwardly and spaced from the wall. Individual strips of insulating fibers are then impaled over the upright legs. Miles places a multiplicity of ceramic fiber strips in side by side relation and bonds one lateral edge to an expanded metal mounting strip. The module is then secured to the wall by round-ended buttons forcibly inserted into respective expanded metal openings.
Severin et al proposes a pleated ceramic fiber blanket utilizing a multiplicity of components including a channel shaped base plate, a pair of rods piercing all pleats and having their ends anchored in tabs secured to the base plate and provided at its corners with J-shaped suspension bolts engageable with pairs of rods mounted on the interior of a furnace wall.